Pre-Stress Modal Analysis with Software Pro Engineering Mechanica

Pre-Stress Modal Analysis with Software Pro Engineering Mechanica

Pro Engineer Mechanica is a user-friendly FEA module of ProE. Like other structural FE analysis Pro Engineer Mechanica can be used as modal analysis software. It has the capability of performing the modal as well as the pre-stress modal analysis. The modal analysis and the pre-stress modal analysis are performed to know the natural frequencies and mod shapes of your ProE model.

How to Perform Pre-Stress Modal Analysis in Pro Mechanica

  • Create the ProE model. Let’s say we need to analyze the block shown below:

  • Go to Applications>Mechanica to switch to the Mechanica module from the standard module. Select Structural as the analysis type.

  • Apply suitable material for the model.

  • You have to apply load now. Apply 100 in lbm/Sec2 at the top surface of the block vertically downward. For that go to insert>force/moment load and a dialog box will open like below:

Pro Mechanica Force Application

We have selected the top surface of the block (the red colored surface) and applied the load (100 in lbm/Sec2) downwards direction.

  • Next, apply the displacement constraints. For that go to insert>displacement constraints and select the bottom surface of the block.

You have to mesh the block now. For that go to AutoGEM> Create and you will get the AutoGEM dialog box like below:

AutoGEM

Click on the “Create” button and the mesh will be generated. Hit the “Close” button.

Go to Analysis> Mechanica Analysis/Studies and you will get the Analysis and Design studies dialog box open like below:

  • Now go to File>New Static of the just opened Analysis and Design Studies dialog box and the Static analysis definition dialog box will open, just press Ok.

  • Click on the Green Flag (start run) of the analysis and design studies dialog box.

  • Next click on the Display Study Status icon. Press the Close button, once the run is complete.

  • Now go to the File> New Prestress > Modal of the Analysis and Design Studies dialog box.

  • Click the Ok button of the analysis definition dialog box.

  • Click the Start run (green flag) and the Display study status icon and press the Close button once the run is complete.

  • Now press the last icon (Review result) of the analysis and design studies dialog box and the Result Window Definition dialog box will appear like below:

Click on the “Create” button and the mesh will be generated. Hit the “Close” button.

Go to Analysis> Mechanica Analysis/Studies and you will get the Analysis and Design studies dialog box open like below:

Pro Mechanica Analysis and Design Studies Dialog

  • Now go to File>New Static of the just opened Analysis and Design Studies dialog box and the Static analysis definition dialog box will open, just press Ok.

  • Click on the Green Flag (start run) of the analysis and design studies dialog box.

  • Next click on the Display Study Status icon. Press the Close button, once the run is complete.

  • Now go to the File> New Prestress > Modal of the Analysis and Design Studies dialog box.

  • Click the Ok button of the analysis definition dialog box.

  • Click the Start run (green flag) and the Display study status icon and press the Close button once the run is complete.

  • Now press the last icon (Review result) of the analysis and design studies dialog box and the Result Window Definition dialog box will appear like below:

Mechanica Modal Analysis Review Result

  • You will see the different natural frequencies of the model. Select any of them and press OK and Show to see the mod shape of that frequency.

For performing only modal analysis you need to follow all the steps explained above except the static analysis. You need not to perform static analysis directly; go to

New> Modal of the Analysis and Design Studies dialog box

and perform the rest of the analysis.

Summary

Modal analysis and pre-stress modal analysis is performed to know the natural frequencies and mod shapes of a ProE model. Pro Engineer Mechanica can be used as modal analysis software for performing quick modal analysis. The example discussed in the Pro Mechanica tutorial is sufficient enough to understand the concept.